Answer: A) The 'lub' sound is caused as the atrioventricular valves close.
Explanation:
USATestprep just answered it
The answer to number 6 is a.
Answer:
rockfall, mudflow, and landslide are three
Explanation:
pls give thanks and brainlist if helped
It is based on shared characteristics
Ecosystems disturbed by a nature will be eventually restored unless it's a really big cataclysm, but most of the ecosystems are now a human caused disturbance. For example there are plenty of species which are already extinct or nearly extinct because of hunting industry.
